This study aims to clarify whether and how the portal sites in wired
Internet environments can enhance their positions as market leaders in the mobile
environment.The result may explain that the user’s trust in the mobile services of
portal sites (the mobile portal services) is related to the site’s quality and the site’s
brand equity significantly and is a mediator to increase the user’s intention to use
mobile portal services. This study also explains that the user’s experience with a
smartphone can encourage portal users to expect that the mobile portal services are
useful and that the experience can link brand equity in certain business environments to trust in the brand in other business environments. Site quality including the
design quality of portal sites can affect the user’s trust in the mobile services of the
portal sites directly and can affect the user’s intention to use the mobile portal
services under certain conditions. Practically, this study suggests that portal sites
should focus on designing and developing more usable sites with high-quality UI
components—convenient menu navigation, a proper UI design, and usable content
rather depend on their current position as the leading companies in the wired
Internet environment.